refactor: migrate prefer_first

[andrew-bekhiet-solid]

Closes #278

[gemini-code-assist]

Code Review

This pull request migrates the prefer_first lint rule and its quick fix (PreferFirstFix) to the standard analyzer plugin APIs, updating the rule, visitor, and fix implementations, and introducing a reflective test suite. The review feedback highlights two critical issues: first, using thisOrAncestorOfType independently for both MethodInvocation and IndexExpression can lead to incorrect replacements in nested expressions, which can be resolved by using thisOrAncestorMatching; second, calling .first on node.argumentList.arguments can cause analyzer crashes when the argument list is empty, which should be avoided by using firstOrNull.

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